Die stacking involves mounting one or more chips on another chip in a single semiconductor package. This process can increase the amount of circuitry that can be housed within a package of a given size, and thus reduces the real estate taken up on a printed circuit board by a chip. Die stacking may also simplify the assembly of printed circuit boards since multiple dies may be attached to a printed circuit board in a single operation. Die stacking also has the potential to improve the electrical performance of devices in which it is used since the interconnections between elements on each of the stacked dies may be shorter than the interconnections that would be required to connect the die elements on a planar surface. This can result in faster signal propagation and may also reduce cross-talk.
While die stacking provides the above benefits, and others, it may also increase the thickness of a given printed circuit board (PCB) or package. In some applications the thickness of a package including the stacked die may be greater than the height available for mounting the package. In those situations, it may be necessary to redesign the product in which the stacked die is to be used or forego the benefits of die stacking. It would be desirable to provide a solution to the above problem which would expand the range of environments in which packages having stacked dies could be used.